The invention relates to a stacking spindle for a phonograph record changing apparatus (hereinafter referred to as a record changer); and more particularly to a record changer having an end-stop function for the playing mode, and an umbrella-type changer spindle having groups of clamping and supporting levers which are accommodated in a tube, which levers upon a command from the automatic changing mechanism are actuated by the changing device so as to perform a mutually coordinated movement. An actuating rod, which is controlled by the changing device, acts on the group of clamping levers through a clamp sleeve which is movable on the rod.
Such a stacking spindle is known from German patent specification No. 11 28 166, to which U.S. Pat. No. 3,081,093 corresponds. The actuating rod then extends from the top to the bottom inside the tube, and a pressure spring ensures that in the normal position the actuating rod is pressed into its highest position. The clamp sleeve is slidably fitted on the actuating rod, and the clamping levers are pivotably journalled to the sleeve in such a way that their lower ends can be pressed out of the tube. An additional pressure spring ensures that the clamp sleeve and the clamping levers on the actuating rod are urged downwards as far as a stop. The supporting levers are directly suspended to the actuating rod and, when the actuating rod is pulled downwards, they can be pivoted inwards by the tube edges. For the end stop function an additional rod is provided which, if there is no longer any record on the stacking spindle, moves further downwards because the clamp sleeve which guides the clamping levers moves downward.
This stacking spindle, which operates with a so-called top load, demands substantial tensile forces, which are to be produced by the changing device. Moreover, the stacking spindle is of comparatively complicated construction, considerable space is needed for the end-stop rod. Finally, a further major disadvantage is that the movement of the supporting levers is rigidly coupled to the movement of the actuating rod. As a result of this, the tolerance on the freedom of movement of the actuating rod is quite limited.